I want to extend RadTextBox by implementing RequiredFieldValidator. I did simillar functionality with asp:textbox :
When I want to inherit from RadTextBox (at line 2: Inherits Telerik.Web.UI.RadTextBox), code stops working with weird error:
Unable to find control id 'txtTest' referenced by the 'ControlToValidate' property of ''.
What I'm doing wrong? Thank you for your help!
Zdenek